Site-specific probing of charge transfer dynamics in organic photovoltaics

Journal Article · Mon Mar 23 00:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4916278· OSTI ID:22398765

Arion, Tiberiu; Roth, Friedrich ^[1]; Neppl, Stefan; Shavorskiy, Andrey; Bluhm, Hendrik; Gessner, Oliver ^[2]; Hussain, Zahid ^[3]; Eberhardt, Wolfgang ^[1]

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1. Center for Free-Electron Laser Science/DESY, Notkestraße 85, D-22607 Hamburg (Germany)
2. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
3. ALS, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

We report the site-specific probing of charge-transfer dynamics in a prototype system for organic photovoltaics (OPVs) by picosecond time-resolved X-ray photoelectron spectroscopy. A layered system consisting of approximately two monolayers of C{sub 60} deposited on top of a thin film of Copper-Phthalocyanine (CuPC) is excited by an optical pump pulse and the induced electronic dynamics are probed with 590 eV X-ray pulses. Charge transfer from the electron donor (CuPC) to the acceptor (C{sub 60}) and subsequent charge carrier dynamics are monitored by recording the time-dependent C 1s core level photoemission spectrum of the system. The arrival of electrons in the C{sub 60} layer is readily observed as a completely reversible, transient shift of the C{sub 60} associated C 1s core level, while the C 1s level of the CuPC remains unchanged. The capability to probe charge transfer and recombination dynamics in OPV assemblies directly in the time domain and from the perspective of well-defined domains is expected to open additional pathways to better understand and optimize the performance of this emerging technology.

• OSTI ID: 22398765
• Journal Information: Applied Physics Letters, Vol. 106, Issue 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
BINDING ENERGY
CHARGE CARRIERS
COPPER COMPLEXES
ELECTRONS
EV RANGE
FULLERENES
LAYERS
PHOTOEMISSION
PHOTOVOLTAIC EFFECT
PHTHALOCYANINES
RECOMBINATION
THIN FILMS
TIME DEPENDENCE
TIME RESOLUTION
TRANSIENTS
VALENCE
X RADIATION
X-RAY PHOTOELECTRON SPECTROSCOPY